Exam 14: Natural Selection and Adaptation Bugs That Resist Drugs

Explain ways in which you could acquire any Staphylococcus aureus infection (not necessarily MRSA)at the gym.

Assume that every time you copy DNA,whether it is bacterial DNA or human DNA,you have the same rate of mutation.If that is the case,explain why bacteria mutate to adapt to their environment much faster than humans.

An organism's ability to survive and reproduce is called the organism's

Which of the following is more fit?

A species of small lizard has three color forms,pale gray,brown,and black.In its original range,the colors of the rocky environment were mixed from pale gray to very dark,and the population had an even mix of all three color forms.The blending of colors with their environment helps the lizards hide from predators.A group of these lizards ended up on an island with all gray rocks.Eventually,only gray lizards remained.This is an example of

All of the following are true of natural selection,EXCEPT

Overprescription of antibiotics and their improper use is a cause of

Describe how ß-lactams function to kill bacteria.Be specific not only about what they do but also about the results.

A bacterium has a gene that creates a ß-lactamase enzyme.It passed that gene to another bacterium it encounters.What is the result of that gene transfer?

If a man fathers a child at 20 years of age,the DNA that was passed on to the child was created 20 years after the zygote that created the man.How many generations of bacteria could be formed in that same 20 years (ignore leap years)? How many more chances of mutation would the bacterial DNA have?

What is decreased as a result of stabilizing selection?

Which of these strains of bacteria (A-E)is most fit in a hospital situation? Explain.

Natural selection is the process that leads to evolution.Natural selection responds to the environment and yields more fit creatures,yet it is said that evolution is NOT goal oriented.How can you reconcile this?

Eighty years ago,a predatory crab was introduced to a region it previously did not inhabit and began preying on a species of marine snail.A scientist was able to locate museum specimens of the snail's shells from prior to the crab's introduction and to compare their thickness-an important factor in how protective the shells are-to the thickness of shells from current snails.Based on the graphs of her results (shown here),what form of evolution/natural selection has taken place?

Natural selection causes

Which of the following people is/are especially vulnerable to illness caused by drug-resistant bacteria?

Staphylococcus aureus is a type of

Which of the following people are at the lowest risk of acquiring MRSA?

A number of mosquito populations today are resistant to specific insecticides,even though those insecticides were highly effective when they were first introduced.Biologists believe that insecticide resistance evolved in mosquitoes because

If a bacterium susceptible to ß-lactam antibiotics were placed in an isotonic solution and exposed to the antibiotics,